Skip to main content
  1. Home
  2. Products & Services
  3. Standards
  4. Standards News Highlights
  5. Standard 521

API Standard 521

API Standard 521, Pressure-Relieving and Depressurizing Systems, provides guidance, recommendations, and alternatives for the design of pressure-relieving and vapor de-pressuring systems at liquefied natural gas terminals, petrochemical facilities, gas plants, and other petroleum production facilities.

API Standard 521 is available for purchase on the API Webstore. 

Stay up-to-date on all API Publications like Standard 521 across an organization with API Standards Online Subscription.

Certification Directories

Free directories listing all of the participants in our certification-related programs.

View All

API Online Subscription Service

This platform gives users the latest updates, references, and comparison tools to ensure safety and compliance.

Get a Quote

Related Products

API Standards Subscription

Access standards, analyze available standards, support your organization with other API initiatives and mitigate risk with the latest change management tools like new standards alerts through this direct licensing platform.

Individual Certification Programs (ICP)

ICP provides the petroleum and petrochemical industries with an independent and unbiased way to evaluate the knowledge and experience of technical and inspection personnel.

Events

API hosts numerous events each year spanning all segments of the industry.
Thank you for Subscribing Unable to Process Request x